1. Field of the Invention
The present invention relates to a full automatic washing machine, and more particularly, to a damper for a full automatic washing machine, which is fitted between a housing and an outer tub of the full automatic washing machine for absorbing, and damping vibration from the outer tub.
2. Background of the Related Art
A related art full automatic washing machine, which carries out all cycles starting from washing to rinsing and spinning automatically, will be explained with reference to FIGS. 1 and 2.
Referring to FIG. 1, the related art full automatic washing machine is provided with a housing 1 having an upper hanger 11 on an upper inside portion, an outer tub 2 having a lower hanger 21 on an outside lower portion and fastened to an inside of the housing 1 for storing washing water, an inner tub 3 rotatably mounted in the outer tub 2 and having a pulsator(not shown) on a bottom for circulating washing water to wash laundry, and a damper 4 fitted between the lower hanger 21 on the outer tub 2 and the upper hanger 11 on the housing 1 for absorbing, and damping vibration and impact from the outer tub 2.
In the meantime, referring to FIG. 2, the damper 4 is provided with a damper bar 41 having upper and lower holders 41a and 41b at upper and lower ends and a caulking part 41c on an upper portion, an upper buffering member 42 caught at the upper hanger 11 on the housing 1 having a through hole 42a at a center for pass through of the damper bar 41, a lower buffering member 43 caught at the lower hanger 21 on the outer tub 2 having an operating hole 43a at a center for pass through of the damper bar 41, and a longitudinal cut-away slot 43c for permitting radial contraction to bring the operating hole 43a into frictional contact with the damper bar 41, a support plate 46 fitted to a lower end of the damper bar 41 such that fall off of the support plate 45 is prevented by the lower holder 41b, a compression coil spring 44 fitted between the support plate 46 and the lower buffering member 43 as an elastic member for elastic supporting of the lower buffering member 43 so that the coil spring is compressed and expanded against vibration and impact transmitted from the outer tub 2 for absorbing the vibration and impact, and a buffer tube 45 fitted to surround the compression coil spring 44 for generating friction force during the compression and expansion of the compression coil spring 44. Therefore, if there is vibration occurred in the washing machine during washing, the vibration is transmitted to the damper 4 through the outer tub 2, and the damper 4 absorbs, and attenuates the vibration by the friction between the lower buffering member 43 and the damper bar 41 and compression and expansion of the compression coil spring 44.
However, the related art damper having the foregoing action has the following problems in view of the structure.
First, in assembly of the damper 4 to the housing 1, under a state a driving device(not shown) and the inner tub 3 are assembled to the outer tub 2, the lower buffering member 43 of the damper 4 is fixed to the lower hanger 21, the housing 1 is covered on the outer tub 2, and the upper buffering member 42 of the damper 4 is fixed to the upper hanger 11, thereby fixing the outer tub 2 to the housing 1. The fixing of the upper buffering member 42 of the damper 4 fixed to the outer tub 2 to the housing 1 is carried out by hand, wherein there are cases frequently occurred, in which the upper buffering member 42 is slipped down to a bottom side by its own weight in a state before the upper buffering member 42 of the damper 4 is fixed to the upper hanger 11 on the housing 1 because there is a slight gap between the through hole 42a in the upper buffering member 42 of the damper 4 and the damper bar 41, with grease applied in the gap for prevention of wear. In this instance, the worker should put his hand through a narrow gap between the housing 1 and the outer tub 2 to reach to the bottom side of the washing machine, pull up the upper buffering member 42, and fix to the upper hanger 11 of the housing 1. In order to solve such a problem in the related art, though the caulking part 41c is formed on the upper portion of the damper bar 41, for catching the upper buffering member 42 so that the upper buffering member 42 is prevented from coming down any more, the formation of the caulking part 41c on the damper bar 41 requires additional fabrication process.
In the meantime, in the full automatic washing machine, there are cases when the outer tub 2 hits inside of the housing 1 due to strong vibration caused by weight of the inner tub 3 itself and the washing water and laundry, if the washing machine is forcibly stopped suddenly. When the outer tub 2 thus hits inside of the housing 1, the impact is transmitted to the lower hanger 21 as it is, to break the lower buffering member 43 as the lower buffering member 43 in a hole 21a of the lower hanger 21 hits onto an inside circumference of the hole 21a. Accordingly, in order to solve the foregoing problems in the related art, a thickness of the lower buffering member 43 is formed thicker, only to increase a possibility of breakage, though the lower buffering member 43 becomes the stronger, and to deteriorate an accuracy of the hole 43a to increase a probability of causing defects due to shrinkage in injection molding.
And, the related art damper has a problem in that there are cases when the lower buffering member comes out of the compression coil spring 44. That is, an eccentric load occurred in the inner tub 3 increases an amplitude of up and down direction vibration of the inner tub 3 and the outer tub 2, together with an amplitude increase of the damper 4, wherein, as shown in FIG. 3, if the damper 4 vibrates excessively, the lower buffering member 43 comes out of the compression coil spring 44, and sits on a top end of the compression coil spring 44, coming down inside of the coil spring no more.
In the meantime, though there is grease applied in the gap between the hole 43a of the lower buffering member 43 and the damper bar 41 for prevention of wear of the hole 43a, the gap is made to be tight for providing an adequate friction between the lower buffering member 43 and the damper bar 41, which can not contain a sufficient amount of grease. In addition to the lack of grease, the heat caused by friction between the lower buffering member 43 and the damper bar 41 drops viscosity of the grease, such that the grease flows down along the damper bar 41, that causes to leave almost no grease in the gap in prolonged use.
Accordingly, the present invention is directed to a damper for a full automatic washing machine that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a damper for a full automatic washing machine, which can prevent falling down of an upper buffering member of the damper from an upper end of the damper bar without addition of a member, such as the caulking part, for improving workability, and damage to a lower buffering member of the damper even if an excessive force caused by a sudden stop of the inner tub and the like is applied to the damper.
Another object of the present invention is to provide a damper for a full automatic washing machine, which can prevent the lower buffering member from coming out of the elastic member even if the inner tub and the outer tub vibrate excessively due to an eccentric force occurred in the inner tub.
Other object of the present invention is to provide a damper for a full automatic washing machine, which can hold the grease applied to the gap between the damper bar and the hole of the lower buffering member for a long time, maintain a damping capability of the damper constant, and prevent wear down of the hole in the lower buffering member.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the damper for a full automatic washing machine includes an upper buffering member fitted to an inside of an upper portion of a washing machine housing, an elastic member under the lower buffering member for elastic supporting of the lower buffering member, and a damper bar for passing through, and connecting the upper buffering member, the lower buffering member, and the elastic member in succession, for damping vibration and impact, wherein the upper buffering member has a through hole for passing the damper bar therethrough with an upper portion diameter equal to or smaller than a diameter of the damper bar, and a lower portion diameter greater than the diameter of the damper bar, and the lower buffering member has an extension projected upward from the upper surface.
And, the lower buffering member has a plurality of reinforcing ribs in an upper portion of the extension, sloped guide ribs extended downward from a bottom thereof for preventing the lower buffering member from coming out of a top of the elastic member, and a hole for passing the damper bar therethrough, with an etched rugged inside surface for containing grease.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.